JPS6254690A - Vacuum sucker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

[Field of Industrial Application] The present invention relates to a vacuum suction device used for automatic transportation and assembly of products and mechanical parts, and in particular, a suction pad made of an elastic body is attached to a holder, and a vacuum suction device is installed inside the suction pad. This invention relates to a vacuum suction device that suctions a workpiece by reducing the pressure. [Summary of the Invention] The present invention is configured to hold a sleeve slidably in the axial direction on a holder to which a suction pad made of an elastic body is attached, and to cover the suction pad with the sleeve. The sleeve is biased toward the work by a spring, and the inside of this sleeve is sealed so that the pressure is reduced in almost the same way as the inside of the suction pad, so that the work can be sucked in the correct posture and , which increases its adsorption power.

[Prior Art 1] Vacuum suction devices are used for conveying and automatically assembling various products. Such a device makes it possible to pick up a workpiece and move it to a predetermined position. The conventional vacuum suction@vtM has a rubber pad attached to the tip of a holder that also serves as a suction vibrator, and suction is performed by sucking the inside of the pad and reducing the pressure. It looks like this. [Problems to be solved by the invention] Since the suction pad of such a vacuum suction device is made of a flexible material such as rubber, it itself positions the workpiece and holds it in a predetermined posture. It has no functionality. Therefore, if the angle of the pad relative to the workpiece is misaligned, or if suction is not performed at the correct position, the workpiece will not be suctioned in the correct posture. In order to prevent such poor suction postures, stoppers and lights for regulating the height have been used, but these have not always been sufficiently effective. In addition, in a vacuum suction device using such a suction pad, the suction force that can be obtained depends on the surface area of the pad, the roughness of the surface of the workpiece, and the like. This adsorption force is generally a much lower value than the theoretical value calculated by Pascal's theorem, and there is a drawback that the desired adsorption force cannot necessarily be obtained. The present invention has been made in view of these problems, and it is an object of the present invention to provide a vacuum suction device that can suction a workpiece in the correct posture and generates a high suction force. . Means for Solving Problem K 1 The present invention provides an apparatus in which a suction pad made of an elastic body is attached to a holder and a workpiece is suctioned by reducing the pressure inside the suction pad. A sleeve is held so as to be able to slide in the axial direction and cover the suction pad, and this sleeve is biased toward the workpiece by a spring, and the inside of this sleeve is held in a manner similar to the inside of the suction pad. It is designed to be sealed so that the pressure is reduced.

[Effect 1] Therefore, according to the present invention, it is possible to suction the workpiece in the correct posture using the sleeve, and the inside of this sleeve is sealed so that the pressure is reduced in the same way as the inside of the suction pad. In addition, this makes it possible to increase the adsorption power. Embodiment] The present invention will be described below with reference to an illustrated embodiment. 1 and 2 show a vacuum suction device according to an embodiment of the present invention, and this vacuum suction device is equipped with a suction pad 10. As shown in FIG. The band 10 is made of rubber and is held at the tip of the holder 11. The holder 11 also serves as a suction vibrator, and an air suction hole 12 extending in the axial direction is formed in the center thereof. Further, a ring-shaped protrusion 13 is formed on this holder 11, and the lower end side of this protrusion 13 serves as a holder 14 for holding the pad 10. Further, the upper side of the ring-shaped protrusion 13 is a fitting part 15, which allows a cylindrical sleeve 16 made of, for example, an aluminum alloy to slide therein. As shown in FIG. 2, a ring-shaped protrusion 17 is formed on the inner circumference of the cylindrical sleeve 16 so as to protrude toward the center in the radial direction. It is fitted into the fitting portion 15 described above. Moreover, this fitting part 15
The gap between and the protrusion 17 is very small, for example 0.0
The value is between 1 and 0.03, which prevents air from leaking. By introducing magnetic fluid into this gap, it is possible to achieve complete sealing without causing friction. Further, the upper surface of the protrusion 17 of this sleeve 16 is adapted to receive a compression coil spring 18. And the male screw 1 on the upper end side of the holding body 11
9 is screwed into a female screw hole 21 formed in the support arm 20, and is fixed to a lock nut 22 on the upper surface of the arm 20. In the above configuration, when the suction device suctions the workpiece 23 and moves it to a predetermined position, air is suctioned through the air suction hole 12 of the holder 11, and the suction device as shown in FIG. First, the suction device is lowered so that the tip of the sleeve 16 comes into contact with the surface of the workpiece 23. Since the tip surface of the sleeve 16 is always perpendicular to the central axis, when the entire circumference of the tip surface of the sleeve 16 properly contacts the workpiece 23, this suction device assumes a correct posture with respect to the workpiece 23. and will be held in a perpendicular position. Note that the tip of the sleeve 16 may be further coated with hard rubber. After the suction device is held in the correct position relative to the workpiece 23 by the sleeve 16, the suction device is lowered in this state as shown in FIG. Then, the sleeve 16 moves upward on the holder 11 against the compression coil spring 18, and the pad 10 comes to face the distal end side of the sleeve 16. Then, this suction pad 10 comes into contact with the surface of the work 23, and the suction operation of the work 23 by this pad 10 is performed. During this suction operation, as described above, the tip of the sleeve 16 first comes into contact with the workpiece 23 (see FIG. 3), and the sleeve 1
A light vacuum is created inside the workpiece 6 and the workpiece 23 is relatively pulled up. Next, it is shown in Figure 4. In this way, the rubber pad 10 is in complete contact with the workpiece 23, and a large suction force is generated. Even when the suction pad 10 and the workpiece 23 are in perfect contact with each other, there is some air leakage or suction in the pad 10, but since the sleeve 16 covers the outside of the pad 10, A weak vacuum is formed between the pad 10 and the sleeve 16, which contributes to the attraction of the workpiece 23. Originally the sleeve 16 was the spring 1
8, which provides a force to push the workpiece 23, but the force generated by the weak vacuum condition conversely increases the suction force of the workpiece 23. By actually adding this sleeve 16,
It has been confirmed that the adsorption force is increased by 10 to 20% compared to the conventional one. This adsorption force F is given by the following equation. F−PπD2/4+P−π (Do 2 D2)/
4 In this equation, P and P' represent the pressure inside the bud 10 and the sleeve 16, and D and Oo represent the effective diameters of the bud 10cf5 and the sleeve 16. As is clear from the formula showing this adsorption force F, the force of the second term, which does not exist in conventional adsorption devices, is increased, and it is theoretically proven that this increases the adsorption force. .

【Effect of the invention】

As described above, in the present invention, the sleeve is held so as to be movable in the axial direction by the holder so as to cover the suction pad, the sleeve is urged toward the workpiece by the spring, and the inside of the sleeve is suctioned. It is designed to be sealed so that the pressure is reduced in almost the same way as the inside of the pad. Therefore, according to the present invention, the sleeve comes into contact with the workpiece before the suction pad, and the sleeve allows the suction device to suction the workpiece in a correct posture. Therefore, it is possible to prevent mistakes in transporting parts, etc., and to perform correct assembly by applying the method to an assembly device. In addition, suction force can also be generated by the sleeve disposed outside the suction pad, thereby making it possible to improve suction efficiency and generate high suction force.

[Brief explanation of the drawing]

FIG. 1 shows a vacuum suction IA according to an embodiment of the present invention! ! FIG. 2 is a longitudinal sectional view of the same, FIG. 3 is a longitudinal sectional view showing the start of the suction operation by this suction device, and FIG.
The figure is a longitudinal cross-sectional view showing a state in which the material is attracted and transported. In addition, in the reference numerals used in the drawings, 10...Adsorption pad 11...Holding body 15...Fitting part 16...Sleeve 18...Compression coil spring 23...Workpiece.

Claims (1)

[Claims] In an apparatus in which a suction pad made of an elastic body is attached to a holder and a workpiece is suctioned by reducing the pressure inside the suction pad, the holder is capable of sliding in an axial direction and covers the suction pad. The sleeve is held in such a manner that the sleeve is urged toward the workpiece by a spring, and the inside of the sleeve is sealed so that the pressure is reduced almost in the same way as the inside of the suction pad. vacuum suction device.